Pages

Tuesday, April 7, 2015

A Shrike of Two Tails (***MEGA***)

It has been a glorious 2014-2015 fall and winter for Siberian vagrants in California, with the highlights being Olive-backed Pipit, Common Scoter, Rustic Bunting, multiple Bramblings (only one chaseable), the returning Falcated Duck, and this bird...whatever it is. First disclosed to the birding public in early March, hundreds of birders have made the trek to scenic and windswept Mendocino coastline to see a young Brown Shrike, a horrifically rare bird, even on Alaskan islands where Sibes aren't something out of the ordinary. Having lifered the Humboldt County bird a few years ago, I wasn't highly motivated to put in the drive time, but since Justine Stahl was visiting and offered to do the drive, I did what I thought was best. Now, bear witness to these horrid (torrid) images that are the fruits of our birding labors.

The bird behaved in a completely different way than the Humboldt bird, in that it was incredibly easy to find (other birders were looking at it when we walked up), it was almost always perched in the open, and it was very active, wagging its tail back and forth, flycatching and frequently procuring huge insects which it appeared to stash in various thickets. It was an immensely rewarding chase, especially since we didn't even get there until well after 1 PM. As one famous birder has said, "Middle of day is best time for make rare bird!".

By the day we saw the bird, a number of birders were becoming very concerned about the shrike. Not for its well-being or anything, but for the fact that it didn't really look like any of the other Brown Shrikes that have shown up in North America, which have all ostensibly been of the subspecies cristatus. In fact, some birders were thinking that this bird didn't really look like any kind of Brown Shrike at all...they were thinking the bird could be a Red-backed Shrike, which would of course be a first North American record. One of the reasons for this is that the bird is molting in new blackish central tail feathers, which can be seen above, lying on top of its old brown tail feathers...most Brown Shrikes do not sport a tail this dark. The bird is in the process of molting in to adultish (SY) plumage, so we are all hoping it will stay for a while longer, and that it will finish molting and then be readily identifiable.

Although this bird is relatively easy to see, getting close to it is another issue, which makes documentation a bit of a challenge. The bird's exact color tones seem to differ significantly depending on angle, lighting, and gear used for photography. Here the bird looks significantly less gray-headed than above, but with the new tail feathers still looking very black. Some observers claim these new feathers are actually brown though, which is one of the many confusing sticking points about this bird.

Look at this stunt...the shrike is completely hiding its new dark tail feathers entirely, showing us nothing but old tail. What this does photo show well is that the bird has a brown rump. An adult Red-backed Shrike has a gray rump. Everyone is waiting with bated breath to see if the rump will begin changing or color, or if it will stay the same.

Strong contrast between the new and old tail feathers seen here. The word on the street is that the bird is now sporting some white at the base of the primaries, which is not evident in any of my flight shots.

So what the hell is this bird? One thing everyone agrees on is that it is not a cristatus Brown Shrike. It could be a bright-backed lucionensis Brown Shrike. It could be a "confusus" Brown Shrike. It could be a dull Red-backed Shrike. It could be a Red-backed X Isabelline Shrike. It is probably one of these things. What do I think? I think birding is hard. It is very unusual that such a popular non-gull rarity gives birders this much trouble, which simply speaks to how completely unfamiliar North American birders are with this species complex.

Here is the shrike, sporting two tails. New, shorter retrices on the right are still growing in (being held further out from the body), longer, retained HY retrices pointing straight down. Here's to the bird sticking around a while longer and letting us know what it truly is. All of these photos were taken on March 28, the bird probably looks a bit different by now.